1. Field of the Invention
The present invention relates in general to low-noise optical probes which use optical energy to determine the characteristics of a medium, and in particular to optical probes having flexible, secure connectors for communicating signals to and from the probe.
2. Description of the Related Art
Electromagnetic, light or acoustic signals with known characteristics, when transmitted through or reflected in a medium, may reveal important information about that medium. In the field of medical testing and diagnosis, for example, light, heat or sound signals may be directed at a patient, transmitted or reflected through the patient's body, and received and compared with the original signal or wave. As a result, information about the patient's condition can be deduced without invasive testing, and information can be gathered continuously with minimal patient discomfort. For example, during surgery, blood oxygen saturation can non-invasively be deduced and continuously monitored.
Typically, reusable and disposable optical probes are employed to measure an amount of transmitted or reflected light through an accessible part of the body, such as a finger, an earlobe, loose skin, a forehead, or the like. For example, reusable and disposable optical probes or sensors having the foregoing characteristics are disclosed and described in U.S. Pat. No. 5,782,757.
The foregoing sensors typically incorporate a light source such as a light-emitting diode (LED) placed on one side of the body part, and a photodetector placed on an opposite side of the body part. The sensor may also connect to external monitoring equipment through a wire or cable. For example, reusable sensors often connect to external monitoring equipment through a permanent, plastic molded connection between the sensor and the cable.
The foregoing sensors suffer from at least several drawbacks. For example, the sensor is often limited to the useful life of the permanent plastic molded wire in that when the wire fails, the sensor is rendered inoperable despite its continuing functionality. Likewise, when the sensor fails, the wire or cable, the cost of which may not be trivial, is also rendered useless. In addition, existing reusable sensors do not have the capability to connect to monitoring equipment in a secure, reusable, yet flexible manner.